When fabrics are laundered, it is frequently desirable to treat them with fabric softeners, not only to soften them, but to give them greater bulk, make them easier to iron, decrease fabric drying time, and reduce static charge. A fabric softener that is commonly used is N-dihydrogenatedtallow-N,N-dimethylammonium chloride (DTMAC), which is both inexpensive and effective as a softener but, on the other hand, has certain deficiencies, such as its yellowing and reducing the washability of the softened fabrics, having inefficient antistatic activity on polyesters, and decreasing the rewettability of the treated fabrics.
Amine oxides, such as N-alkyl-N,N-dimethylamine oxides, are also effective fabric softeners; and fabrics softened with them have been found to have better rewettability than fabrics softened with DTMAC. Thus, it has been proposed to use amine oxides in combination with DTMAC to provide better rewettability than can be obtained with DTMAC as the sole fabric softener. However, when the surfactants have been combined in laundry detergents or in laundry dryer sheets, improved rewettability has not been obtained; and, when an amine oxide such as N-octyl-N,N-dimethylamine oxide is combined with DTMAC in a laundry rinse, the rewettability of the fabric is intermediate to the rewettability of a fabric softened with the amine oxide alone and the rewettability of a fabric softened with DTMAC alone.